Just starting on converting my camera raw files to DNG. I've got lots of files I've edited in Bridge and ACR, so there are lots of associated XMP files. I just want to make doubly-sure that I don't have to do anything special to insure all that data gets incorporated into the DNG files that Adobe DNG Converter creates, and that once the conversions are done, I can remove the .xmp's from my hard drive along with the original raw files.(And, yes, everything is backed up and archived.)

I wonder why you have XMPs on the first place. *If* ACR creates XMPs, then the adjustments are not recorded in the DNG file. This happens if the DNG file is write protected.

Pick any DNG file from yesterday or earlier, check the date of last modification. Load it in ACR, make some changes and save it ("Done"). Check the date of last modification: it should be updated. If not, then an XMP file has to be there, EXCEPT if you selected "Save image settings in Camera Raw database", in which case you deserve what you get.

You're misunderstanding me. I've JUST STARTED converting my raws to DNG's. The XMP's I'm talking about are ones that Bridge generated in the past whenever I manipulated a raw file (in ACR). I'm confirming that all that pre-existing XMP stuff gets properly incorporated into the DNG I generate from the raw file.

But to answer the question directly, all metadata is stored within the DNG file. This includes all data that is normally stored in XMP files associated with raw files. The DNG file does not require the XMP file unless, for some reason, you change the DNG file to a read-only file.

Yes, Ctein, the sidecar XMP metadata is included in the DNG header. If you edit the DNG with Camera Raw, then CR will update the editing metadata within the DNG. (The exception is if you've made the DNGs read-only, in which case CR will go back to using sidecar XMPs.)

Ctein, I'm guessing your DNGs are corresponding to a camera model that the OS does not recognize, or they are missing some metadata that the OS is looking for. In general, the OS does not render previews unless it recognizes the camera model.